In a multi-flow heat exchanger 100 (condenser) shown in FIG. 8, refrigerant flowing into a first header tank 101b is supplied to plural tubes 101a to be distributed into each of the tubes 101a, and condensed liquid refrigerant flowing out of the tubes 101 is collected into a second header tank 101c. However, in this case, it is difficult to uniformly distribute the refrigerant from the first header tank 101b into the tubes 101a. When a distribution performance of refrigerant flowing into the tubes 101a is deteriorated, radiating performance of the heat exchanger 100 cannot be sufficiently improved.
To overcome this problem, in a condenser described JP-2002-130866, an orifice throttle is provided in a longitudinal middle portion of the second header tank 101c to decompress refrigerant flowing in the second header tank 1d, so that it can restrict a refrigerant amount flowing into the lower side tubes 101 separated from a refrigerant inlet from being reduced. However, in this condenser, because the orifice throttle is formed in a plate member within a header tank, refrigerant from the orifice throttle flows to a downstream space mainly in the longitudinal direction of the header tank.
In an actual condenser of a refrigerant cycle, gas refrigerant introduced into the condenser 100 is not entirely condensed in the tubes 101a, and gas refrigerant may be discharged from a part of the tubes 101a. In this case, gas refrigerant more than a necessary, degree is stored in a receiver, and a liquid refrigerant amount more than a necessary amount flows into an evaporator from the receiver. Accordingly, liquid refrigerant may be discharged from the evaporator to a compressor, and high-pressure equipments including the compressor may be damaged.
In contrast, in a vapor compression refrigerant cycle without the receiver, gas-liquid mixed refrigerant flows into an evaporator from the condenser, and heat-absorbing capacity of refrigerant in the evaporator is decreased.